Suction cleaner



Jan. 8, 1935. w. H. KIT-ro 1,986,976

SUCTION CLEANER Filed April 19, 1955 INVENTOR VVV/Yam H? #o ATTORNEY Patented Jen. s, 1935 l 1,986,976

UNITED STATES PATENT OFFICE SUCTION CLEANER William H. Kitto, Canton, Ohio, assignor to The Hoover Company, North Canton, Ohio, a corporation of Ohio Application April 19, 1933, Serial No. 666,799

6 Claims. (Cl. 15-16) The present invention relates in general to sucmeans are necessary for such motors and often tion cleaners, and more particularly to a new and take the form of a motor-cooling fan positioned novel construction for cooling the driving motor in the motor casing. In the machine constructed in a suction cleaner. More specifically the inin accordance with the present invention this advention comprises a construction by which cooling ditiona-l fan has been eliminated and in its place air is drawn through the cleaner motor into the use has been made of the suction-creating power suction-creating part of the suction cleaner for c'f the main suction-creating fan of the cleaner. the purpose of cooling the motor, means being Means have been provided to overcome the undeprovided to prevent the return to the motor of sirable effect of back pressure in the dust bag.

10 dirt-laden air at the end of the cleaning oper- If a direct opening were left from the fan chamber ation. to the motor casing this back pressure would 10 It is an object ofthe present invention to proeffect the movement of dirt-laden air from the vide a new and improved suction cleaner. It is a fan chamber to the motor casing resulting in a further object to provide new and improved modeposition of undesirable foreign matter on the tor-cooling means in a suction cleaner. Still anmotor. 15 other object is the provision, m a suction cleaner, Referring again to the drawing a sufficient porof means to draw cooling air from the motor castion of a. modern suction cleaner is illustrated to ing into the low suction area of the fan chamber clearly illustrate the present invention. A motor 101' the Purpose 0f 0001in8 the motor. A Still furcasing 1 is secured at the rear of a fan chamber 2,

ther object is a provision in a suction cleaner, of the front wall 3 of the motor casing functioning 20 a construction which permits the suction-creatas the rear wall of the fan chamber. A nozzle 4 ing fen t0 draw 00011118 ail' thrOugh the mOtOr, is interiorly connected to the fan chamber 2 menS being Provided t0 Prevent the 110W 0f air through an eye or inlet 5, and there is provided from the fan chamber back into the motor casan exhaust outlet 6 on the fan chamber to which ing. A still further object is the provision of is attached a, suitable dust bag 7. 25 means which automatically CIOSeS the C001ing air Positioned within the motor casing 1 is the passageway from the motor casing to the suctionelectric driving motor for the cleaner, the arma- Creting mea-HS when the m0t0l iS dead- TheSe ture 8 being rotatably supported upon the shaft 9 and Other more Speeic Objects Will appeal UDO!! which is itself carried at its forward end by a redng the fOllOWng SDeCCatiOn and Claims. bearing 10 in the wall 3 and at its rear end by 30 and upon considering in connection therewith the bearing 11. The motor neId is indicated by the attached drawing t0 which they relate. reference character 12 and is non-rotatably Referring now to the drawing in which a premounted within the casing 1, ferred embodiment 0f the present inventien iS The suction-creating fan 13 is carried by the disclosed: motor shaft 9 forward of the wall 3 in the vfan 35 ating fan which in turn eects the movement of and the Ian Chamber by radial openings 14 in the Figure 1 i5 Partial Vertical cross .Section chamber 2, and upon the rotation of the motor thmugh 9' Suction cleaner casing in Whch the this fan functions to draw cleaning air from the Present invention is embodied? nozzle 4 through the fan` chamber inlet 5 and Figure 2 is s' section upon the une z z'of Fig exhaust it at high pressure through the exhaust ure 1, and also upon the line 2-2 of Figure 3; t be Ot d 40 Figure 3 is an enlarged Showing of the air pas outlet 6 and into dust bag 7. I 1s to n e 40 that bearing 10 is provided with a seal 10 which insagoewtg ioto. xgglrgsfhaft at the point it emerges cooperates to prevent the movement of dirt laden air through the bearing and into the motor casing.

mixf-,l is a second embodiment of the present In the construction according to the present in- Flgure 5 is g showing 0f 9, suction cleaner in vention the motor shaft 9 is counter-bored from 45 which the present invention is embodied. its end within the fan chamber 2 to a point well Suction cleaners today are provided with g high within the motor casing 1, and is interiorly conspeed electric motor which drives a suctiomcrenected to both the interior of the motor casing 0 cleaning air through the cleaner nozzle, the un motor casing and 15 in the fan chamber, the latchamber, and into the dirt receptacle or dust bag, ter openings being provided in the nut 16 which It is desirable that the electric motor be substan.. seats upon the end of the motor shaft to secure tially completely incased in order that disturbed the fan 13 in-place. It is to be noted that the foreign matter will not lodge therein. Cooling openings 15 in the fan chamber are positioned at 55 the point of reduced pressure therein, that is, at Ithe center of the suction-creating fan.

Y Within the motor casing seals 17, 17 are mounted on shaft 9 by springs 18, 18 and are held by these springs over the openings 14, 14. The force exerted by the springs is sufficient to hold the seals in place when the motor is not rotating but upon the motor reaching a certain speed centrifugal force acting upon the seals throws them outwardly against the spring force thereupon permitting unhindered access to the interior of the hollow motor shaft to air within the motor casing. An encircling cup or shield 19 encloses the seals 17, 17 in 'spaced relationship and functions to limit their outward radial movement under centrifugal force.

In the operation of this embodiment of the invention with the motor in the static condition seals 17, 17 are seated against the openings 14, 14 and the interior of the motor casing is sealed from theinterior of the fan chamber. Upon the rotation of the motor, as when the cleaner is being used, upon reaching a predetermined speed centrifugal force throws the seals 17, 17 outwardly against the inward force exerted by the springs 18 and cooling air is drawn across the'motor, having entered the casing at the opening 1a in the rear thereof. This cooling air enters the hollow motor shaft through the openings 14, 14 and passes therethrough into the low pressure point of the fan chamber, enteringthat body through the openings 15, 15. So long as the motorcontinues to rotate at its normal operating speed this movement of cooling air continues. When the motor current is turned 01T, however, the motor speed is reduced and the spring force exerted by the springs 18, 18 becomes greater than centrifugal force and the seals are forced against the openings 14, 14. This last operation prevents the movement of dirt laden air from the fan charnber 2 under the back pressure force exerted by the air pressure existing in the dust bag 7.

Referring now to Figure 4, in particular, a slightly modied form of the present invention is disclosed which differs from the embodiment aforedescribed in that the openings 15, 15 are positioned within the hub of the suction-creating fan 13 and are alined with openings 20, 20 in the hub to permit the passage of air as in the first embodiment. This construction permits the use of a driving pulley 21 at the forward end of the motor 'shaft and makes possible the use of the invention in suction "cleaners embodying positively driven agitating means. In other particu- 'lars this embodiment of the invention is the same as that aforedescribed.

I claim: Y

1. In a suction cleaner, a fan chamber, a motor casing, a motor including a rotatable shaft in said casing, said shaft being extended into said fan chamber and being hollow from a point in said casingto a point in said chamber, a fan carried casing, said shaft being extended into said fan chamber and being hollow from a point in said casing to a point in said chamber, a fa'n carried by saidy shaft in said chamber, said shaft being interiorly connected by radial openings to said casing and chamber, a seal for one of said' openings, a spring urging said seal into sealing relationship and opposing the centrifugal force exerted by said seal upon the rotation of said shaft, the strength of saidspring being such that said seal moves to an open position upon said shaft reaching a predetermined speed of rotation.

3. In a suction cleaner, a dirt-laden-air passageway including a nozzle, a fan chamber, and an exhaust outlet; a fan in said fan chamber to create a reduced pressure in said nozzle to draw air therethru and exhaust it thru said outlet; a

driving motor positionedadjacent said fan chamber, the shaft of said motor being extended into said chamber and carrying said fan; and a passageway connecting the interior of said motor to the nozzle side of said fan and dirt-laden-air passageway for the purpose of conveying cooling air from said motor.

4. 'Ihe construction dened by the preceding claim characterized by the fact that said coolingair passageway extends from said motor to the inlet of said fan chamber.

5. The construction recited in the second preceding claim characterized in thatl means are provided to automatically close said cooling air passageway when said motor rotates at less than a predetermined speed.

6. In a suction cleaner, a nozzle, a fan chamber, and an exhaust outlet, a fan in said fan chamber to create a reduced pressure in said nozzle to draw air therethru and exhaust it thru said outlet, a driving motor positioned adjacent said fan chamber, the shaft of said motor extended into said chamber and carrying said fan, said shaft being hollow from a point in said motor to a point of low pressure on the nozzle side 0f said fan chamber for the purpose of conveying cooling WILLIAM H. KITTO. 

